1. Field of the Invention
The present invention relates to recording apparatuses and recording methods, and specifically to a recording apparatus and a recording method that are capable of recording images on a recording medium without leaving a margin at the edge thereof, that is, capable of performing so-called borderless printing.
2. Description of the Related Art
These days, inkjet printers capable of recording images with the beauty and quality of silver salt photographs are examples of color inkjet recording apparatuses. On the other hand, since digital cameras are widely available, there are increasing demands for easily printing images taken with a camera as card-sized or L-sized prints, or large-sized prints, such as A4-sized or A3-sized prints, using an inkjet printer. Some recording apparatuses for printing photographs are configured to perform so-called borderless printing, which produces prints without a white border, like silver salt photographs.
Inkjet printers use one of the following two methods to perform borderless printing. The first method is to prepare a recording medium (recording paper) with a tear-off section on the four edges of the medium, allow images to be recorded on the tear-off section as well as on the inside section, and then trim the tear-off section after recording. The second method is to prepare a recording medium without a tear-off section, and allow images to be recorded off the edges of the recording medium (that is, record images on the entire surface of the recording medium so as not to leave a margin at the edges of the medium).
The second method is mainly used these days, as it has an advantage in that there is no need for an additional operation, such as the trimming of a tear-off section after recording. In both of the two methods, an area on which images are recorded and which is off the edges of the resultant recording medium with images printed thereon (for example, an area on which ink droplets have been ejected and which lies outside the recording medium with a size corresponds to the size of printed material to be ultimately obtained) will be hereinafter referred to as an “overflow area” or “outside area”.
However, borderless printing according to both of the two methods has a problem in that it takes more time in performing recording operations than that in the case of printing of a normal print with borders. For example, if recording is performed, by serial scanning, on recording media of the same size, the width of the recording area in the direction of scanning for printing a photo with borders is smaller, by the width of the borders at both ends, than the width of the recording medium in the scanning direction. On the other hand, for printing a photo without borders, the width of the recording area in the scanning direction is larger than the width of the recording medium in the scanning direction by the width of the above-described overflow (outside) areas at both ends. That is, compared to the printing of a photo with borders, borderless printing involves the additional amount of scanning by the width of borders and overflow (outside) areas at both ends of the recording medium. This increases the total amount of time required for performing a predetermined amount (such as one page) of recording.
FIG. 3 shows the relationship between a carriage operation and a line feed operation in a borderless printing operation of a known example.
As shown in FIG. 3, in borderless printing, the width of the recording area is set to be larger than that of the recording medium (recording paper). This is to ensure reliable recording on the entire surface of the recording medium even if the recording medium is fed obliquely, and provides an effective method to allow image recording to be performed without leaving a margin at the edge of the recording medium. A recording area that extends off the recording medium corresponds to the overflow (outside) area described above.
Referring to FIG. 3, a carriage accelerates from a stopped state, and moves at a constant speed across the recording area to perform recording by ejecting ink droplets from a recording head. After moving at a constant speed across the recording area, the carriage decelerates and stops for time period tcp1. Then, the carriage accelerates again, moves at a constant speed, and performs recording on the subsequent recording area. The time interval between recording on a recording area and recording on the subsequent recording area includes a deceleration control period, a stop control period, and an acceleration control period for the carriage. Thus, the total time required for these control operations is time period tpp1 (>time period tcp1). That is, the time from the end of recording on one recording area to the start of recording on the next recording area is time period tpp1 as shown in FIG. 3.
In a serial inkjet printer, a line feed operation is performed during the interval between recording on one recording area and the next recording area (area adjacent to the previous recording area in the feed direction). This line feed operation is performed during time period tpp1 as in FIG. 3.
That is, line feed control is performed such that the line feed operation starts immediately after the completion of recording on the previous recording area, in other words, simultaneously with the start of the deceleration of the carriage. The line feed control is also performed such that the line feed operation ends at the start of recording on the next recording area, in other words, at the end of the acceleration of the carriage.
Therefore, the line feed operation starts after the completion of recording on an overflow (outside) area near the recording end position within the recording area, and the line feed operation ends before the start of recording on an overflow (outside) area near the recording start position within the recording area. Thus, in the known example, the period of recording on the overflow (outside) area does not overlap with that of the line feed operation. In other words, recording on the overflow (outside) area is not executed simultaneously with the line feed operation.
On the other hand, in Japanese Patent Laid-Open No. 2003-53953, a carriage is provided with a sensor for detecting the edge of a recording medium. In this case, control is performed, in borderless printing, such that a recording operation is not performed on areas off the edge. However, in such a structure, there are problems in that the addition of the sensor raises costs, increases the size of the carriage due to the positional relationship between the sensor and a recording head (particularly in the scanning direction), thereby causing an increase in the range of scanning.